[patch-early-RFC 10/10] LTTng - s390 instrumentation

From: Mathieu Desnoyers
Date: Wed Dec 05 2007 - 22:02:23 EST


Changelog :
- added syscall entry/exit instrumentation.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxx>
---
arch/s390/kernel/entry.S | 10 ++++++++--
arch/s390/kernel/entry64.S | 10 ++++++++--
arch/s390/kernel/ptrace.c | 6 ++++++
arch/s390/kernel/sys_s390.c | 2 ++
arch/s390/kernel/traps.c | 17 +++++++++++++++++
arch/s390/mm/fault.c | 6 ++++++
6 files changed, 47 insertions(+), 4 deletions(-)

Index: linux-2.6-lttng/arch/s390/kernel/traps.c
===================================================================
--- linux-2.6-lttng.orig/arch/s390/kernel/traps.c 2007-11-28 09:27:27.000000000 -0500
+++ linux-2.6-lttng/arch/s390/kernel/traps.c 2007-11-28 09:33:55.000000000 -0500
@@ -5,6 +5,7 @@
* Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Author(s): Martin Schwidefsky (schwidefsky@xxxxxxxxxx),
* Denis Joseph Barrow (djbarrow@xxxxxxxxxx,barrow_dj@xxxxxxxxx),
+ * Portions added by T. Halloran: (C) Copyright 2002 IBM Poughkeepsie, IBM Corporation
*
* Derived from "arch/i386/kernel/traps.c"
* Copyright (C) 1991, 1992 Linus Torvalds
@@ -307,6 +308,9 @@ static void __kprobes inline do_trap(lon
interruption_code, signr) == NOTIFY_STOP)
return;

+ trace_mark(kernel_arch_trap_entry, "trap_id %ld ip #p%lu",
+ interruption_code & 0xffff, instruction_pointer(regs));
+
if (regs->psw.mask & PSW_MASK_PSTATE) {
struct task_struct *tsk = current;

@@ -327,6 +331,7 @@ static void __kprobes inline do_trap(lon
die(str, regs, interruption_code);
}
}
+ trace_mark(kernel_arch_trap_exit, MARK_NOARGS);
}

static inline void __user *get_check_address(struct pt_regs *regs)
@@ -437,6 +442,9 @@ static void illegal_op(struct pt_regs *
if (regs->psw.mask & PSW_MASK_PSTATE)
local_irq_enable();

+ trace_mark(kernel_arch_trap_entry, "trap_id %ld ip #p%lu",
+ interruption_code & 0xffff, instruction_pointer(regs));
+
if (regs->psw.mask & PSW_MASK_PSTATE) {
if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
return;
@@ -501,6 +509,7 @@ static void illegal_op(struct pt_regs *
do_trap(interruption_code, signal,
"illegal operation", regs, &info);
}
+ trace_mark(kernel_arch_trap_exit, MARK_NOARGS);
}


@@ -521,6 +530,9 @@ specification_exception(struct pt_regs *
if (regs->psw.mask & PSW_MASK_PSTATE)
local_irq_enable();

+ trace_mark(kernel_arch_trap_entry, "trap_id %ld ip #p%lu",
+ interruption_code & 0xffff, instruction_pointer(regs));
+
if (regs->psw.mask & PSW_MASK_PSTATE) {
get_user(*((__u16 *) opcode), location);
switch (opcode[0]) {
@@ -565,6 +577,7 @@ specification_exception(struct pt_regs *
do_trap(interruption_code, signal,
"specification exception", regs, &info);
}
+ trace_mark(kernel_arch_trap_exit, MARK_NOARGS);
}
#else
DO_ERROR_INFO(SIGILL, "specification exception", specification_exception,
@@ -585,6 +598,9 @@ static void data_exception(struct pt_reg
if (regs->psw.mask & PSW_MASK_PSTATE)
local_irq_enable();

+ trace_mark(kernel_arch_trap_entry, "trap_id %ld ip #p%lu",
+ interruption_code & 0xffff, instruction_pointer(regs));
+
if (MACHINE_HAS_IEEE)
asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));

@@ -659,6 +675,7 @@ static void data_exception(struct pt_reg
do_trap(interruption_code, signal,
"data exception", regs, &info);
}
+ trace_mark(kernel_arch_trap_exit, MARK_NOARGS);
}

static void space_switch_exception(struct pt_regs * regs, long int_code)
Index: linux-2.6-lttng/arch/s390/kernel/sys_s390.c
===================================================================
--- linux-2.6-lttng.orig/arch/s390/kernel/sys_s390.c 2007-11-28 09:27:27.000000000 -0500
+++ linux-2.6-lttng/arch/s390/kernel/sys_s390.c 2007-11-28 09:33:55.000000000 -0500
@@ -150,6 +150,8 @@ asmlinkage long sys_ipc(uint call, int f
struct ipc_kludge tmp;
int ret;

+ trace_mark(ipc_call, "call %u first %d", call, first);
+
switch (call) {
case SEMOP:
return sys_semtimedop(first, (struct sembuf __user *)ptr,
Index: linux-2.6-lttng/arch/s390/mm/fault.c
===================================================================
--- linux-2.6-lttng.orig/arch/s390/mm/fault.c 2007-11-28 09:27:27.000000000 -0500
+++ linux-2.6-lttng/arch/s390/mm/fault.c 2007-11-28 09:33:55.000000000 -0500
@@ -5,6 +5,7 @@
* Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Author(s): Hartmut Penner (hp@xxxxxxxxxx)
* Ulrich Weigand (uweigand@xxxxxxxxxx)
+ * Portions added by T. Halloran: (C) Copyright 2002 IBM Poughkeepsie, IBM Corporation
*
* Derived from "arch/i386/mm/fault.c"
* Copyright (C) 1995 Linus Torvalds
@@ -169,6 +170,7 @@ static void do_no_context(struct pt_regs
fixup = search_exception_tables(regs->psw.addr & __FIXUP_MASK);
if (fixup) {
regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
+ trace_mark(kernel_arch_trap_exit, MARK_NOARGS);
return;
}

@@ -334,6 +336,9 @@ do_exception(struct pt_regs *regs, unsig
*/
local_irq_enable();

+ trace_mark(kernel_arch_trap_entry, "trap_id %ld ip #p%lu",
+ error_code & 0xffff, instruction_pointer(regs));
+
down_read(&mm->mmap_sem);

si_code = SEGV_MAPERR;
@@ -415,6 +420,7 @@ bad_area:
tsk->thread.prot_addr = address;
tsk->thread.trap_no = error_code;
do_sigsegv(regs, error_code, si_code, address);
+ trace_mark(kernel_arch_trap_exit, MARK_NOARGS);
return;
}

Index: linux-2.6-lttng/arch/s390/kernel/entry.S
===================================================================
--- linux-2.6-lttng.orig/arch/s390/kernel/entry.S 2007-11-28 09:27:27.000000000 -0500
+++ linux-2.6-lttng/arch/s390/kernel/entry.S 2007-11-28 09:33:55.000000000 -0500
@@ -270,8 +270,10 @@ sysc_do_svc:
sysc_nr_ok:
mvc SP_ARGS(4,%r15),SP_R7(%r15)
sysc_do_restart:
+ l %r8,__TI_flags+3(%r9)
+ n %r8,BASED(.Lc_tif_syscall_trace_or_audit_or_kernel_trace)
+ ltr %r8,%r8
l %r8,BASED(.Lsysc_table)
- tm __TI_flags+3(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
l %r8,0(%r7,%r8) # get system call addr.
bnz BASED(sysc_tracesys)
basr %r14,%r8 # call sys_xxxx
@@ -398,7 +400,9 @@ sysc_tracego:
basr %r14,%r8 # call sys_xxx
st %r2,SP_R2(%r15) # store return value
sysc_tracenogo:
- tm __TI_flags+3(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
+ l %r8,__TI_flags+3(%r9)
+ n %r8,BASED(.Lc_tif_syscall_trace_or_audit_or_kernel_trace)
+ ltr %r8,%r8
bz BASED(sysc_return)
l %r1,BASED(.Ltrace)
la %r2,SP_PTREGS(%r15) # load pt_regs
@@ -1063,6 +1067,8 @@ cleanup_io_leave_insn:
.L0x030: .short 0x030
.L0x038: .short 0x038
.Lc_1: .long 1
+.Lc_tif_syscall_trace_or_audit_or_kernel_trace:
+ .long _TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_KERNEL_TRACE

/*
* Symbol constants
Index: linux-2.6-lttng/arch/s390/kernel/entry64.S
===================================================================
--- linux-2.6-lttng.orig/arch/s390/kernel/entry64.S 2007-11-28 09:27:27.000000000 -0500
+++ linux-2.6-lttng/arch/s390/kernel/entry64.S 2007-11-28 09:33:55.000000000 -0500
@@ -263,7 +263,9 @@ sysc_do_restart:
larl %r10,sys_call_table_emu # use 31 bit emulation system calls
sysc_noemu:
#endif
- tm __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
+ l %r8,__TI_flags+7(%r9)
+ n %r8,BASED(.Lc_tif_syscall_trace_or_audit_or_kernel_trace)
+ ltr %r8,%r8
lgf %r8,0(%r7,%r10) # load address of system call routine
jnz sysc_tracesys
basr %r14,%r8 # call sys_xxxx
@@ -387,7 +389,9 @@ sysc_tracego:
basr %r14,%r8 # call sys_xxx
stg %r2,SP_R2(%r15) # store return value
sysc_tracenogo:
- tm __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
+ l %r8,__TI_flags+7(%r9)
+ n %r8,BASED(.Lc_tif_syscall_trace_or_audit_or_kernel_trace)
+ ltr %r8,%r8
jz sysc_return
la %r2,SP_PTREGS(%r15) # load pt_regs
la %r3,1
@@ -1023,6 +1027,8 @@ cleanup_io_leave_insn:
.align 4
.Lconst:
.Lnr_syscalls: .long NR_syscalls
+.Lc_tif_syscall_trace_or_audit_or_kernel_trace:
+ .long _TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_KERNEL_TRACE
.L0x0130: .short 0x130
.L0x0140: .short 0x140
.L0x0150: .short 0x150
Index: linux-2.6-lttng/arch/s390/kernel/ptrace.c
===================================================================
--- linux-2.6-lttng.orig/arch/s390/kernel/ptrace.c 2007-11-28 09:27:27.000000000 -0500
+++ linux-2.6-lttng/arch/s390/kernel/ptrace.c 2007-11-28 09:33:55.000000000 -0500
@@ -723,6 +723,12 @@ out:
asmlinkage void
syscall_trace(struct pt_regs *regs, int entryexit)
{
+ if (!entryexit)
+ trace_mark(kernel_arch_syscall_entry, "syscall_id %d ip #p%ld",
+ (int)regs->gprs[2], instruction_pointer(regs));
+ else
+ trace_mark(kernel_arch_syscall_exit, "ret %ld", regs->gprs[2]);
+
if (unlikely(current->audit_context) && entryexit)
audit_syscall_exit(AUDITSC_RESULT(regs->gprs[2]), regs->gprs[2]);


--
Mathieu Desnoyers
Computer Engineering Ph.D. Student, Ecole Polytechnique de Montreal
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/